possible breakages: * `FN_HEADER` on cold are no longer `s/-/_/` -- this is so that cold functions can rebuild the headers as they were when they came in on the request (fdks, specifically), there's no guarantee that a reversal `s/_/-/` is the original header on the request. * app and route config no longer `s/-/_/` -- it seemed really weird to rewrite the users config vars on these. should just pass them exactly as is to env. * headers no longer contain the environment vars (previously, base config; app config, route config, `FN_PATH`, etc.), these are still available in the environment. this gets rid of a lot of the code around headers, specifically the stuff that shoved everything into headers when constructing a call to begin with. now we just store the headers separately and add a few things, like FN_CALL_ID to them, and build a separate 'config' now to store on the call. I thought 'config' was more aptly named, 'env' was confusing, though now 'config' is exactly what 'base_vars' was, which is only the things being put into the env. we weren't storing this field in the db, this doesn't break unless there are messages in a queue from another version, anyway, don't think we're there and don't expect any breakage for anybody with field name changes. this makes the configuration stuff pretty straight forward, there's just two separate buckets of things, and cold just needs to mash them together into the env, and otherwise hot containers just need to put 'config' in the env, and then hot format can shove 'headers' in however they'd like. this seems better than my last idea about making this easier but worse (RIP). this means: * headers no longer contain all vars, the set of base vars can only be found in the environment. * headers is only the headers from request + call_id, deadline, method, url * for cold, we simply add the headers to the environment, prepending `FN_HEADER_` to them, BUT NOT upper casing or `s/-/_/` * fixes issue where async hot functions would end up with `Fn_header_` prefixed headers * removes idea of 'base' vars and 'env'. this was a strange concept. now we just have 'config' which was base vars, and headers, which was base_env+headers; i.e. they are disjoint now. * casing for all headers will lean to be `My-Header` style, which should help with consistency. notable exceptions for cold only are FN_CALL_ID, FN_METHOD, and FN_REQUEST_URL -- this is simply to avoid breakage, in either hot format they appear as `Fn_call_id` still. * removes FN_PARAM stuff * updated doc with behavior weird things left: `Fn_call_id` e.g. isn't a correctly formatted http header, it should likely be `Fn-Call-Id` but I wanted to live to fight another day on this one, it would add some breakage. examples to be posted of each format below closes #329
Fn is an event-driven, open source, functions-as-a-service compute platform that you can run anywhere. Some of its key features:
- Open Source
- Native Docker: use any Docker container as your Function
- Supports all languages
- Run anywhere
- Public, private and hybrid cloud
- Import Lambda functions and run them anywhere
- Easy to use for developers
- Easy to manage for operators
- Written in Go
- Simple yet powerful extensibility
The fastest way to experience Fn is to follow the quickstart below, or you can jump right to our full documentation, API Docs, or his us up in our Slack Community!
Quickstart
Pre-requisites
- Docker 17.05 or later installed and running
- A Docker Hub account (Docker Hub) (or other Docker-compliant registry)
- Log Docker into your Docker Hub account:
docker login
Install CLI tool
The command line tool isn't required, but it sure makes things a lot easier. There are a few options to install it:
1. Homebrew - MacOS
If you're on a Mac and use Homebrew, this one is for you:
brew install fn
2. Shell script
This one works on Linux and MacOS (partially on Windows):
curl -LSs https://raw.githubusercontent.com/fnproject/cli/master/install | sh
This will download a shell script and execute it. If the script asks for a password, that is because it invokes sudo.
3. Download the bin
Head over to our releases and download it.
Run Fn Server
Now fire up an Fn server:
fn start
This will start Fn in single server mode, using an embedded database and message queue. You can find all the configuration options here. If you are on Windows, check here. If you are on a Linux system where the SELinux security policy is set to "Enforcing", such as Oracle Linux 7, check here.
Your First Function
Functions are small but powerful blocks of code that generally do one simple thing. Forget about monoliths when using functions, just focus on the task that you want the function to perform.
First, create an empty directory called hello and cd into it.
The following is a simple Go program that outputs a string to STDOUT. Copy and paste the code below into a file called func.go.
package main
import (
"fmt"
)
func main() {
fmt.Println("Hello from Fn!")
}
Now run the following CLI commands:
# Initialize your function
# This detects your runtime from the code above and creates a func.yaml
fn init
# Set your Docker Hub username
export FN_REGISTRY=<DOCKERHUB_USERNAME>
# Test your function
# This will run inside a container exactly how it will on the server
fn run
# Deploy your functions to the Fn server (default localhost:8080)
# This will create a route to your function as well
fn deploy --app myapp
Now you can call your function:
curl http://localhost:8080/r/myapp/hello
# or:
fn call myapp /hello
Or in a browser: http://localhost:8080/r/myapp/hello
That's it! You just deployed your first function and called it. To update your function
you can update your code and run fn deploy myapp again.
User Interface
We also have an open source graphical user interface for Fn. It's very easy to use, simply run the command below:
docker run --rm -it --link fnserver:api -p 4000:4000 -e "FN_API_URL=http://api:8080" fnproject/ui
For more information, see: https://github.com/fnproject/ui
Learn More
- With our Fn Getting Started Series, quickly create Fn Hello World applications in multiple languages. This is a great Fn place to start!
- Visit Fn tutorials for step by step guides to creating apps with Fn . These tutorials range from introductory to more advanced.
- See our full documentation
- View all of our examples
- View our YouTube Channel
- View our API Docs
Get Help
- Ask your question on StackOverflow and tag it with
fn - Join our Slack Community
Get Involved
- Join our Slack Community
- Learn how to contribute
- See milestones for detailed issues
